Crank 1 rotates about fixed axis x-x and is connected by turning pair A-A to link 2 which, in turn, is connected by turning pairs to circular sliders 3 and 4. Sliders 3 and 4 move along circular guides a. When crank 1 rotates about axis x-x, sliders 3 and 4 oscillate in circular guides a of the base about axis y-y under the condition that the axes of all the kinematic pairs intersect in a single point.
$1499$SC,4L$